LuxS/AI-2， as an interspecific communication quorum sensing (QS) system， is commonly found in lactic acid bacteria (LAB)， which can regulate the probiotic properties of LAB， including biofilm formation， acid tolerance， bile salt tolerance， cells adhesion. In this study， LAB with production of AI-2 signal molecule was screened using strain Vibrio harveyi BB170 reporting method. The expression of luxS gene was detected by PCR sequencing. Moreover， the probiotic properties of high-yield AI-2 LAB were evaluated by acid resistance， bile salt resistance， antibacterial and cells adhesion. The results showed that ten strains of LAB producing AI-2 were screened from two hundred strains LAB. Among them， Lactobacillus plantarum SCT-2 had strong ability to produce AI-2 signal molecule. The luxS gene was further verified exist in strain SCT-2. The survival rates of acid and bile salt resistant in strain SCT-2 were 14%-92% and 63%-89%， respectively. The antibacterial diameter of strain SCT-2 ranged from 17.50 mm to 19.43 mm. The number of adhesion cells of strain SCT-2 was 102 CFU/cell. Compared to LAB with low production AI-2， the biofilm formation， acid tolerance， bile salt tolerance， inhibitory rate and cell adhesion of strain SCT-2 increased by 111.4%， 8%， 15%， 26.7% and 197%， respectively. These results indicated that luxS gene was the key gene of AI-2 signal synthesis. LuxS/AI-2 quorum sensing system improves the biofilm forming ability， acid tolerance， bile salt tolerance antibacterial ability and cells adhesion of LAB. It will provide a theoretical basis for the development of LAB biological agent with good probiotic properties.